Steam-boiler



(No Model.) 'asuma-sheet 1.

B. BRAZELLE. STEAM 'BOILBR` No. 458,413, y Patented Aug. 25, 1891.

f. ii 3 M r 3 l L L (No Model.) 4 Sheets-Sheet 2.

RRAZBLLE.

STEAM BOILBR.

No. 458,413. Patented Aug. 25,' 1891.

WEI/17265565:

(No Model.) 4 Sheets- Sheet 3.

B. BRAZELLB.

STEAM BOILBR.

No. 458,413'. @tema Aug. 25, 1891.

vnl'. mms Punks co., mam-mno., wnmmrrou, n. c.

(No Model.) 4 Sheets--Sheet 4.

B. BRAZELLE.

STEAM BOILBR.

No. 458,413. Patented Aug. 25,1891.

l llllm, lll

UNITED STATES PATENT OFFICE.

BENJAMIN BRAZELLE, OF ST. LOUIS, MISSOURI.

STEAM-BOILER.

SPECIFICATION forming part of Letters Patent No. 458,413, dated August 25, 1891.

Serial No. 311,433. (No model.)

To all whom it may con/cern:

Be it known that I, BENJAMIN BRAZELLE, of St. Louis, in the State of Missouri, have inventeda certain new and useful Improvement in Steam-Boilers, of which improvement the following is a specication.

The object of my invention is to facilitate and expedite the generation of steam by the provision ot' simple and eiective means for causing the rapid and continuous circulation of Water in a steam-boiler over the surfaces to which heat is applied.

To this'end my invention, generally stated, consists lin the combination of a shell, an internal tire-box, a series of fire-tubes passing longitudinally through the shell, and a series of external circulating-tubes extending from the upper portion of the water-space to and opening vertically and directly into the firebox casing.

The improvement claimed is hereinafter fully set forth.

In the accompanying drawings, Figure lis a vertical longitudinal central section through a steam-boiler embodying my invention; Fig. 2, a horizontal section through the same at the line .fr :t of Fig. 1; Fig. 3, a vertical longitudinal section through a boiler, illustrating a modied form of connection of the upper ends of the circulating-tubes; and Figs. et and 5, horizontal sections through the same at the lines y g/ and e z, respectively, of Fig. 3.

My invention is herein illustrated as applied in a boiler of the vertical tubular type having a cylindrical shell 1,which is connected at its lower end by an annular sheet 2 to a firebox casing 3 of a diameter greater than that of the main portion of the boiler. An inside fire-box 4, having a suitable grate 5 located near its bottom, is connected in the usual manner to the tire-box casing 3, and a series of lire tubes or lues 6 passes through the boiler fromthe crown-sheet 7 of the re-box to the head 8, which closes the opposite end of the boiler, the tubes 6 delivering the products ot combustion from the fire-box into a smokebox or uptake 9, to which a proper stack or discharge-flue is connected.

While I have shown and described a multiple series of fire-tubes as being the preferred construction, it will be obvious that a single flue or lues of larger diameter may, if preferred, be employed, and would constitute a mechanical equivalent. A steam-supply pipe lO leads from the upper portion ot the steamspace of the boiler to a desired point of delivery.

In order to produce and maintain a continuous and rapid circulation of water in the boiler, and thereby to' correspondingly promote and expedite the generation ot steam therein by continually presenting different portions of the contained body of Water to the heated surfaces of the tubes G and crown-sheet 7, I provide a series of circulating-tubes 11, which are located on theoutside of the shell l, their upper ends communicatingtherewith a short distance below the normal water level Aline of the boiler, and their lower ends opening into the water-space inclosed by the firebox casing 3 a short distance below the annular sheet or head 2, by which said casing is connected to the shell. The circulating-tubes pass through the sheet 2, with which they make tight joints to prevent leakage ofmwater, and are extended below the head, as shown, to prevent the entrance of upward currents of water during rapid steam generation.

As shown in Figs. l and 2, the circulatingtubes are connected directly to the shell at their upper ends, the shell being enlarged in diameter similarly to the lire-box from the level of the upper ends of the circulating'- tubes to the top head 8 of the boiler. The enlarged upper portion of the shell,whichin closes the steam-space and affords increased volume therefor, is connected with the main portion of the shell by an annular sheet 14,

into which the upper ends of the circulatingtubes are expanded in the usual manner, and through which a direct downward passage for water into the circulating-tubes is afforded, as indicated by the arrows in Fig. 1.

The construction illustrated in Figs. 3 to 5, inclusive, diers from that of Figs. 1 and 2 in the particular that the shell lis of uniformi diameter above the tire-box casing in lieu of being enlarged at and near its upper end, and the upper ends of the circulating-tubes 11 are connected to the shell below the normal waterlevel through the intermediation of separate fittings or heads 12, which are provided with ICO suitable anges, through which they are bolted or riveted to the shell. The'circulating-tubes are secured tightly in openings on the lower sides of the heads, and in order to admit of the insertion of an expander for setting the tubes opposite openings are formed in the upper sides of the heads, which openings are closed by caps 13.

In operation the heat imparted to the series of nre-tubes 6 by the products of combustion is transmitted, to the Water, which immediately adj oins the fire-tubes, thereby causing the formation of a series of ascending currents of Water, which are rendered rapid and continuousby the provision of avenues for corresponding descending currents through the external circulating-tubes ll, which, not being exposed to heat, offer no resistance to the downward passage of the columns of Water which they contain. The Water as displaced by heat is thus successively replaced by colder Water, and a thorough and rapid circulation is insured, by which steam is freely and rapidly generated, and the heat of the escaping products of combustion effectivel y and economically utilized. The employment-of the enlarged fire-box casing and circulating-tubes enables the volume of Waterspace to be materially reduced relatively vto that of boilers of the ordinary construction,` and by the enlargement of the upper portion of the shell increase of steam-space may be effected, as desired.

The rapid steam-generating capacity of the boiler resultant upon the facilities it affords for free and thorough circulation enables a comparatively large horse-power to be aord! ed Within a relatively small compass, which,

under many conditions of service, isa mattei' of'lnaterial importance in adaptation to required duty.

I claim as my invention and desire to secure by Letters Patent- 1. The combination, in a steam-boiler, of a shell, an internalre-box, a fire-box casing of enlarged diameter relatively to the shell, a series of internal fire-tubes, and a series of external circulating-tubes extending from the upper portion of the Water-space of the shell to the enlarged fire-box casing and leading vertically and directly. thereinto, substantially as set forth.

2. The combination, in a steam-boiler, of a shell, an internal fire-box, a lire-box casing of enlarged diameter relatively to the shell, an annular head connecting the shell and irebox casing, a series of internal {ire-tubes, and a series of external circulatingtubes connected at their upper ends to the shell and passing vertically through the annular head into the Water-space of the lire-box, substantially as set forth.

3. The combination, in a-steam-boiler, of a shell, an internal fire-box, a series of-internal fire-tubes, a series of external circulatingtubes opening'at their lower ends into the Water-space of the tire-box, a series of heads or fittings connected directly'to the shell and to the upper ends of the circulating-tubes, and caps closing openings in saidheads above the circulating-tubes, substantially as set forth.

BENJAMIN BRAZELLE.

Witnesses:

J. M. LEWIS, M. G. REYNoLD. 

